The Development of Transparent Photovoltaics

Transparent photovoltaics (TPVs), which combine visible transparency and solar energy conversion, are being developed for applications in which conventional opaque solar cells are unlikely to be feasible, such as windows of buildings or vehicles. In this paper, we review recent progress in TPVs along with strategies that enable the transparency of conventional photovoltaics, including thin-film technology, selective light-transmission technology, and luminescent solar concentrator technology. From fundamental research to commercialization of the TPV, three main perspectives should be considered: (1) high-power conversion efficiency at the same average visible transmittance; (2) aesthetic factors, which should not detract from applications such as buildings and vehicles; and (3) feasibility for real-world applications, including modularization and stability evaluation. We present the distinct analysis criteria for these main perspectives and discuss their importance. We also discuss possible research directions for the commercialization of TPVs

Targeting metastatic breast cancer with peptide epitopes derived from autocatalytic loop of Prss14/ST14 membrane serine protease and with monoclonal antibodies

Background In order to develop a new immunotherapeutic agent targeting metastatic breast cancers, we chose to utilize autocatalytic feature of the membrane serine protease Prss14/ST14, a specific prognosis marker for ER negative breast cancer as a target molecule. Methods The study was conducted using three mouse breast cancer models, 4 T1 and E0771 mouse breast cancer cells into their syngeneic hosts, and an MMTV-PyMT transgenic mouse strain was used. Prss14/ST14 knockdown cells were used to test function in tumor growth and metastasis, peptides derived from the autocatalytic loop for activation were tested as preventive metastasis vaccine, and monoclonal and humanized antibodies to the same epitope were tested as new therapeutic candidates. ELISA, immunoprecipitation, Immunofluorescent staining, and flow cytometry were used to examine antigen binding. The functions of antibodies were tested in vitro for cell migration and in vivo for tumor growth and metastasis. Results Prss14/ST14 is critically involved in the metastasis of breast cancer and poor survival rather than primary tumor growth in two mouse models. The epitopes derived from the specific autocatalytic loop region of Prss14/ST14, based on structural modeling acted as efficient preventive metastasis vaccines in mice. A new specific monoclonal antibody mAb3F3 generated against the engineered loop structure could reduce cell migration, eliminate metastasis in PyMT mice, and can detect the Prss14/ST14 protein expressed in various human cancer cells. Humanized antibody huAb3F3 maintained the specificity and reduced the migration of human breast cancer cells in vitro. Conclusion Our study demonstrates that Prss14/ST14 is an important target for modulating metastasis. Our newly developed hybridoma mAbs and humanized antibody can be further developed as new promising candidates for the use in diagnosis and in immunotherapy of human metastatic breast cancer.This work is supported in part by the National Research Foundation (NRF) grant funded by the Korea government (MEST) (No. 2013R1A1A2009892 and No. 2017R1A2B4008109) and Inha Univeristy Research Grant awarded to MGK and (No. 2015R1A2A1A15054021) to SHK

Field-induced Radial Junction of Crystalline Silicon with Al2O3 Formed via Atomic Layer Deposition for Optoelectronic Devices

School of Energy and Chemical Engineering (Energy Engineering)clos

Field???Induced Radial Junction for Dopant???Free Crystalline Silicon Microwire Solar Cells with an Efficiency of Over 20%

Radial junctions on crystalline silicon (c-Si) microwire structures considerably reduce the diffusion length of photoinduced minority carriers required for energy generation by decoupling light absorption and carrier separation in orthogonal spatial directions. Hence, radial junctions mitigate the need for high-purity materials, and thus reduce the fabrication cost of c-Si solar cells. In this study, the formation of dopant-free radial junctions from atomic layer deposition (ALD) of Al2O3 on an n-c-Si microwire surface is reported. ALD-Al2O3 generates a p(+) inversion layer, which eventually forms the radial junction on the n-c-Si surface. The width of depletion region induced by the p(+) inversion layer is calculated from PC1D simulation as 900 nm. The fabricated dopant-free radial junction c-Si solar cells exhibit a power conversion efficiency of 20.1%, which is higher than those of previously reported microwire-based radial junction solar cells. Notably, internal quantum efficiencies of over 90% are obtained in the 300-980 nm wavelength region, thereby verifying the successful formation of radial junctions

ITO-free carrier selective contact for crystalline Si solar cells

Carrier selective contacts (CSCs) have been proposed to replace the conventional p-n junction because CSCs yield selective hole and electron collections through the negative- and positive-polarity contacts, respectively. For CSCs solar cells, indium tin oxide (ITO) is essential in order to collect the carriers through CSCs because of their relatively low conductivity. However, ITO film formed by sputter deposition leads to serious performance degradation of the CSCs solar cells due to parasitic absorption of ITO and plasma damage during sputtering. In this work, we designed ITO-free transparent metal electrode that can effectively collect carriers separated from the interface between molybdenum oxide (MoOx, hole contact) and c-Si. Although inversion layer in MoOx/c-Si interface has high sheet resistance, we demonstrated that the electrical loss can be minimized in our electrode design. Our micro-scale metal electrode significantly minimizes the optical losses compared to the ITO electrode. In addition, the metal electrode formed by the thermal evaporation prevents sputtering damage, leading to no electrical degradation at the MoOx/Si interface. With this optimized metal electrode, we could obtain the remarkable PCE enhancement of the MoOx/c-Si solar cell achieving a PCE of up to 16% higher than that with the ITO electrode. Thus, the use of our designed metal contact to construct an ideal front electrode presents a unique opportunity to develop highly efficient c-Si solar cells with CSCs